70-75% of France and German broadband connections are DSL, versus 22% in the U.S. The copper networks are mostly depreciated, and copper-loop unbundling has created a lot of competition. But that's also why internet in those countries is so slow. According to Akamai, just 18% of French broadband connections are above 15 mbps, versus 48% of U.S. connections. Copper is also a complete dead-end, technology wise.
Cable in those countries is not super cheap. Kabel Deutschland's gigabit service has a non-promo price of 69.99 euro ($80): https://translate.google.com/translate?hl=en&sl=de&u=https:/.... Comcast's non-promo pricing is $105, which is a bit more expensive in nominal terms, but cheaper as a percentage of net adjusted disposable income (which is 33% higher in the U.S. than in Germany).
You also need to account for differences in labor costs. Broadband isn't like an iPhone, where it's the same product made in China whether you buy it in the U.S. or in Germany. It's a service, like a hotel stay or restaurant meal. Labor to build, maintain, operate, and support the network is a huge part of the cost of broadband, and skilled labor is significantly more expensive in the U.S. than in Germany or France. That's one of the things that makes pricing comparisons between the U.S. and say Romania completely specious. You can buy a 2-ride subway ticket in Bucharest for $1.22--that doesn't tell you anything about what's a reasonable price for a subway ticket in D.C. The $10/month cost for gigabit fiber in Romania is equivalent to $80/month in the U.S.